Pressure vessels have been used to store various types of fluids under various levels of pressurization in order to achieve a number of useful ends. Some common examples and applications include, without limitation, power washers, propane tanks, pneumatic tools, scuba tanks, fire extinguishers, pesticide sprayers, and the like. The market has increasingly demanded lighter weight pressure vessels capable of holding fluids under a higher level of pressure. Lighter weight pressure vessels are generally easier to handle and transport. Further, higher pressure fluids generally translate to greater potential energy. Stated simply, the higher the pressure of the fluid in the vessel, the more work that can be done from a single tank.
Traditional pressure vessels have necessarily been spherically or cylindrically shaped to withstand the stresses created by pressurization. Pressurized fluids exert hydrostatic forces (i.e., substantially the same in all directions), so spherical or cylindrical shaped tanks have provided a means for storing such fluids efficiently because the curved surfaces reduce the number of potential stress concentrations that would otherwise be present. However, spherical or cylindrical shaped pressure vessels do not necessarily make efficient use of available space.
Other known pressure vessels have been designed into non-spherical or non-cylindrical shapes, though such pressure vessels require the use of complex internal supports to facilitate their external shape. Such supports must be configured to the particular shape of the vessel and thus are difficult and costly to manufacture. Further, such internal supports often result in significantly increased weight.
Regardless, to provide a factor of safety, the outer shells of traditional pressure vessels (spherical, cylindrical, or otherwise) are generally made with a higher thickness based on a factor of safety over the weakest area of the pressure vessel. Additionally, traditional pressure vessels often fail in a catastrophic manner, which can cause significant damage and injury. Therefore, what is needed is a pressure vessel capable of being formed into various shapes that is relatively easy to manufacture, is relatively low weight, and fails in a graceful manner.
The present invention is a pressure vessel capable of being formed into various shapes that is relatively easy to manufacture, is relatively low weight, and fails in a graceful manner. The present invention is a pressure vessel comprising an inner matrix placed within an outer shell. The outer shell and the inner matrix may be configured to receive a fluid via an inlet/outlet device. The inlet/outlet device may permit the selective introduction and/or release of the fluid and may be configured to receive a number of adapters configured to facilitate the selective introduction and release of the fluid. In exemplary embodiments, separate inlet/outlet device may be used for the introduction and release of the fluid respectively.
Regardless, the inner matrix may substantially fill the outer shell and may comprise a series of substantially spherical voids. Said voids may be inter connected so as to create apertures at their respective points of contact such that fluid may travel between the voids. This may create passageways through the inner matrix for the fluid to travel from the inlet/outlet device and fill the entire pressure vessel. In exemplary embodiments, the voids are arranged in a face centered cubic configuration to form a nearly closed cell lattice where the apertures comprise filleted edges to reduce or eliminate stress concentrations. The inner matrix and outer shell may be comprised of various materials, however, in exemplary embodiments the inner matrix is integrally formed with the outer shell and both are comprised of the same material. 3-D printing may be used to integrally form the inner matrix with the outer shell.